He said submitting the letter "felt pretty good" and that he has 54 days left to serve.

A representative for Clapper's office told NBC News that he "signed his letter as required by all appointed Administration officials but is finishing out his term."

Clapper has said in interviews with NBC News over the last year that he was counting down the days to stepping down at the end of President Obama's final term in office. He started as a young intelligence office reporting to his father in Vietnam, NBC News reported.